Question

Pls answer these questions ASAP

Answer 1

From the given descriptions and dimensions, we have;

6. 2000 cm²

7. 81 m²

8. a. 138 m²

b. 538 m²

c. 62 cm²

9. $107.25

Which method can be used to calculate the surface areas and cost?

6. Type of box = Open box with no lid

Side length of the box = 20 cm

Therefore;

Number of faces of the box, painted = 5

Area of a face of the box = 20² = 400

• Area of the surface painted, A = 5 × 400 cm² = 2000 cm²

7. Area of the plastic to cover one book, A, is found as follows;

A = 2 × 20 × 15 + 2 × 3 × 15 + 2 × 20 × 3

Which gives;

• A = 600 + 90 + 120 = 810

The area of plastic needed to cover 1000 books is therefore;

Total area = 1,000 × 810 cm² = 810,000 cm²

Conversion of cm² to m² gives;

• 1 m² = 10,000 cm²

Therefore;

A = 810,000 cm² = 810,000 cm² × 1/10,000 m²/cm² = 81 m²

• The area of plastic needed to cover 1000 books is A = 81 m²

8. The surface areas are;

a. A = 2 × 3 × 6 + 5 × 6 + 7 × 6 + 2×3×(3+7)/2 = 138

• The surface area is 138 m²

b. A = 2 × 15 × 5 + 2×(10×5 + (6×8)/2) + 2×8×15 = 538

A = 150 + 148 + 240 = 538

• The surface area is 538 m²

c. From the congruent marks, we have;

A = 5 × 3 × 3 + 5×1×3 + 2×1×1 = 62

• The surface area is 62 cm²

9. From the congruent markings, we have;

A = 2 × (1.5 × 1.5 + (1.5 × 1.3)/2) + 5×2×1.5

A = 6.45 + 15 = 21.45

Surface area of a the canvas, A = 21.45 m²

Cost per unit area of the canvas, c = $5

Cost of the canvas for the tent, C, is therefore;

• C = $5/m² × 21.45 m² = $107.25

Learn more about the finding the surface area of solids here:

brainly.com/question/9478251

#SPJ1